Automatic fire alarm



Sept. 1930. c, QRMSBY 1,775,777

AUTOMATIC FIRE ALARM Filed May 2, 1929 s Sheets-Sheet 1 //VVE/VTOR. Can/v1.5a .6. Owner.

Arr'rs Sept. 1930- c. E. ORMSBY AUTOMATIC FIRE ALARM Filed May 2, 1929 3 Sheets-Sheet 2 //vr/v roe CHA IP45; E. Oemsa y. WM

P 16, c. E. ORMSBY 1,775,777

' AUTOMATIC FIRE ALARM Filed May 2 1929 3 Sheets-Sheet 3' IIYVEN r02. CHARLES E. 019/155)- adm fm Patented Sept. 16, v1930 CHARLES EDWARD ORMSBY, OF TORONTO,

PATENT on let:

ONTARIO, CANADA, ASSIGNOR TO HERBERT CARSON, OF TORONTO, ONTARIO, CANADA AUTOMATIC FIRE ALARM Application filed May 2, 1929. Serial No. 359,941.

This invention relates to improvements in automatic fire alarms and the object of the invention is to provide an improved fire alarmof simple and lnexpensive construction whichwill be positive in operation and which may be conveniently and at small cost installed and which will be equally suitable for small installations such as homes aswell as for larger buildings;

A further object is to provide such a device which will be readily adapted to give practically any desired type of alarm so that the signal maybe made very distinc tive for indicating fire and not be confused with other noises.

A further object is to devise an improved mechanism for operating and controlling the signal, which will be more generally adaptable and suitable for use as a fire alarm than those hitherto devised. V

A further objectis to provide a novel and improved form of brake mechanism for controlling the signal operating mechanism.

The invention consists inthe construction and arrangement, all as hereinafter more particularly described and illustrated in the accompanying drawings in which,

Figure 1 shows a front elevation of one form in which the invention may be'applied.

Figure 2 is a side elevation of Figure 1.

1 Figure 3 is a front elevation of the interior portions, showing the mechanism for actuating the signal. 1

. Figure 4 is a side elevation of Figure 3, one of the side plates of the frame 16 being removed; V.

Figure 5 is a detached fragmentary view of a modified form of mechanism for actuat-,

ing the signal showing some of the parts.

Figure 6 is an edge. elevation of one ofthe signal operating gears shown in Figure 5.

Figure 7 is a diagrammatic view of certain parts as used'in'a further modified embodiment of the invention. 7

In the drawings like characters of reference indicate corresponding parts in the different views. i i In the form illustrated in Figs. 1 to 1inelusive, the apparatus is mounted within a casing A which comprises, a lower circular portion 10 from which extends upwardly a portion 11. The front of the portion 10 is, formed with a circular opening 12 and within the casing is mounted a circular gong element 13 registering with the opening 12: The front face of the portion 11 is open and is adapted to be closed by a removable plate 14 which plate is provided withan opening covered by a perforated plate 15.

Within the portionll is mounted a ;suitable frame 16 in which is mounted a spring operated gear train indicated collectively by the 18131361;B and which constitutes signal actuating means as will be hereinafter ,eX-

plained. Pivotally mounted within the frame 16 is a-spindle 17 to which isrigidly secured a depending arm 18, the lower end of which carries a hammer strike the gong 13.

7 Also rigidly secured to extending upwardly therefrom is an arm 20.

A tension spring2L-hasone end secured to the arm 20 and the otherendsecured to the framelfi so that this spring-normally tends to draw the arm 20 to theleft in Fig. 4 and urge the hammer. 19 towards the gong 13.-

The gear train B is of the usual clock work type'vand c omprisesthe gear 22 which is rigidly secured u'ponthe winding shaft 23 which carries the usual casing 2-1: in which the main spring 25 is mounted, the end-of this spring being secured to the frame 16 at 26.; The spring 25 is wound by a suitable key engaging the squared end 27'of the shaft23. Also mounted within the frame16 are,

further spindles-28,- 29, 30, 31 and 32. Mounted upon thecspindlef 28 is apinion 33 and a gear 34. 'Mounted' upon the spindle 29 is a pinion 35iand a gear 36. Mounted;

upon the spindle30 is a pinion 37 and-a. gear 38 and mounted upon the spindle 31 is a .pinion'39-and abrake wheel 40 theperiphery ofwhich formsa smooth annular brake surface. Mounted upon the spindle 32 is "a gear 41 and two diametricallyopposed cams 42. 'Thevarious members of the gear train B are connected in the usualv clockworkmanner so'that the gear 22 meshes with the pinion'33, the gear 84 with the-pinion '35, the gear 36,wit'h the pinion 37 the GEORGE" j 19 adapted to. the s imue 1'? and gear 38 with the pinion 39 and the gear 34 with the gear 41, the connection, it will be evident, being such that the rotational speed progressively increases through the gear train from the gear 22 to the brake wheel 40 so that the brake wheel 40 will rotate at relatively high speed while the gear 22 will rotate at relatively low speed. Also the gear 34 will rotate at relatively low speed as compared with the brake wheel 40.

A spring actuated brake shoe 43 is nor mally held in braking engagement with the annular brake surface of the brake wheel 40. This brake shoe is formed as part of a bent spring secured to the frame 16 at 44, this spring being bent intermediately at 45, which bent portion 45 extends through the opening in the front of the plate 14 and is located behind the cover plate and this bent portion 45 constitutes thermostatic means for releasing the brake shoe 43 from braking engagement with the brake wheel 40 as will be presently explained.

If desired, a cord 46 may be secured to the arm 18 (see Figs. 1 and 2) in order to throw the signal out of operation temporarily, or for manually operating the hammer.

Also a stop screw 47 (see Fig. 4) may be provided for adjusting the force of the hammer blow upon the gon In the modification shown in Fig. 5 the entire construction of the signal is practically the same as that shown in Figs. 1 to 4 inclusive, with the exception that the gear 21 is dispensed with and also the cams 42 and pins 48 are provided on the gear 34 for actuating the signal in place of the cams 42, as will be later described.

In the modification shown in Fig. 7, the mechanism for operating the signal is identical with that shown in Figs. 1 to 4 inclusive, except that a different manner of releasing the brake shoe 43 is used. In this case the brake shoe 43 is released by means of an r electro-magnet 49, the brake shoe being provided with an armature 50 adapted for attraction by this electro-magnet. The electromagnet 49 is connected in an electric circuit C. The source of current may be either a battery 51 or any other desired source.

In parallel connection within this circuit C are thermostatically operated switches 52 which may be of any desired type and are merely indicated diagrammatically in the view. The operation of this modification will be described later.

The operation of the signal is as follows:

The casing A would be placed in any desired location, and when the spring 25 is wound up, it will be apparent that it will. provide a spring actuated means for driving the various gears of the gear train B.

Normally the brake shoe 43 will be springheld in braking engagement with the annular peripheral surface of the brake wheel 40 so that all the gears will be at rest. In the case of fire, upon the application of heat to the bent portion 45 of the spring, this will stretch and will disengage the brake shoe 43 from braking engagement with the brake wheel 40 so that the gear train will be free to rotate.

The rotation of the intermediate gear 34, which is rotated at relatively low speedas compared with the brake wheel 43, will rotate the cams 42, which during their rotation will strike the arm 20 and oscillate this arm against the tension of the spring 21 and move the hammer 19 away from the gong. As each cam 42, in its rotation clears the arm 20, the spring 21. will oscillate the arm 18 sharply in the opposite direction towards the gong which it will strike and give a signal.

In this way a series of distinct intermittent signals will be struck on the gong which may 0 made as loud as desired, and which due to the nature of the signal will be very clear. loud and distinct so as not to be readily mistaken for an ordinary buzzer type of hell which is in common use and might easily be mistaken for a signal other than lire.

In the form shown in Fig. 5, the operation is practically the same as that shown in Figs. 1 to 4 with the exception that the gear 41 and cams 42 are dispensed with and the hammer is operated by the engagement of the pins 48 on the gear 34 striking the hammer arn. During the operation in this case the hammer would normally be urged towards the gong in the same manner as in the form already described, by means of a tension spring 53.

The operation of the brake shoe in this modification is identical. with that already described in the forms shown in Figs. 1 to 4 inclusive. In the forms shown in Figs. 1 to (i inclusive the signal is operated by the presence of heat adjacent to the casing A, but if desired the invention may be made applicable to buildings where it is desired to have a number of thermostats placed at any desired position throughout the building, so that the presence of fire in any of these portions of the building would operate the signal and this is accomplished by the form shown in Fig. 7.

In this case, the construction of the casing A and the signal'operating mechanism comprising the gear train 13 would be identical with that already described and the brake shoe 43 would normally be held in braking engagement with the brake wheel 40.

In this case, however, an electro-magnet 49 is used in connection with the brake shoe and is placed in the electric circuit C, which circuit extends throughout the building in the form shown. This circuit is ordinarily open so that the electro-magnet is not encrgized and the brake shoe 43 in braking engagement with the brake wheel 40. Upon the application of heat to any of the thermostats 52, the arms of these thermostats are extended and will close the circuit C to energize the electro-magnet 49, which will then attract the armature and disengage the brake shoe 43 from baking engagement with the brake wheel 40 so that the elements of the gear train B will rotate and the signal will be immediately operated.

An important feature of the present invention is the provision of the brake wheel 40 which is provided with an annular peripheral braking surface so that practically any desired signal operating means may be employed to give any desired form of signal, as the manner in which the hammer 19 is operated is practically independent of the form of this braking element Whereas in former signals this was not the case.

l/Vhile the invention has been shown and described in the form of a hammer striking a gong, it mightbe equally applicable to any other type of signal, as for instance the hammer and gong might be dispensed with and a siren type of signal employed.

From the foregoing it will be apparent that the invention provides a fire alarm of extremely efficient form and which will have wide application and which should prove extremely valuable for the purpose intended.

Various modifications may be made in this invention without departing from the spirit thereof or the scope of the claims, and therefore the foregoing specification is to be taken as illustrative only and not in a limiting sense, and it is desired that only such limitations shall be placed thereon as are disclosed in the prior art or are set forth in the accompanying claims.

What I claim as my invention is z-- 1. An automatic fire alarm comprising an alarm signal, spring means for actuating said signal, a rotatory brake element operatively connected to the signal actuating means, said 3 brake element formed with an annular brake surface, and a brake shoe for the brake element normally contacting therewith, said brake shoe being operable upon the application of a predetermined amount of heat therei to to move out of contact with said brake element. r

2. An automatic fire alarm comprlslng an connected to the signal actuating means, said brake element formed with an annular brake surface, a brake shoe for the brake element,

v normally contacting, therewith, said brake shoe constituting a thermostat and being operable to move out of contact with said brake element at a predetermined temperature.

3. An automatic fire alarm comprising an alarm signal, a spring operated gear train, signal actuating'means associated with the gear train, a rotatory brake element operatively connected; 1 with: the :gean ;:train and formed with-an annular brake surface,and a brake shoe for the brake element normally contacting: therewith, said brake shoe being formed with an annular brake surface, nae spring applied brake shoe normally engaging the brake element, and being operable upon the application of a predetermined amount of heat thereto to disengage said brake element.

5. An automatic fire alarm comprising an alarm signal, a spring operated gear train, signal actuating means associated with the gear train, a brake wheel operatively connected to the gear train and formed with an annular peripheral brake surface, a spring applied brake shoe normally engaging the annular peripheral brake surface of the brake wheel, said brake shoe constituting a thermostat and being operable to disengage said brake wheel at a predetermined temperature.

6. An automatic fire alarm according to claim L in which the brake shoe is in the form of a spring finger formed with a bend intermediately thereof, thefree end of the finger forming a brake shoe normally held against the brake element, said finger adapted under the action of heat to stretch and disengage the brake shoe from braking engagement with the brake element.

7 An automatic fire alarm comprising a gong element, a spindle, an arm rigidly connected at one end to the spindle and carrying a hammer at its other end adapted to strike the gong, a second arm rigidly secured to the spindle, spring means normally urging the two arms in one direction, a spring operated gear train, rotatory elements operated by the gear train, and adapted to intermittently strike the second arm to oscillate it and the hammer against the action of the controlling spring, a rotary brake element operatively connected with the gear train and. formed with an annular brake surface, a spring applied brake shoe normally engaging the brake element, and thermostatically controlled means for releasing the brake shoe.

8. An automatic fire alarm comprising an alarm signal, means for actuating said signal, brake means for controlling said actuating means, said brake means belng operable upon the application of a predetermined amount of heat'thereto to release said actuating means.

9. An automatic fire alarm comprising an alarm signal, spring means for actuating said signal; a rotatory brake element operatively connected to the signal actuating means, said brake element formed with an annular brake surface, a spring applied brake shoe normally engaging the brake element, said brake shoe being in the form of a spring finger-formed with a bend intermediately thereof, the free end of the finger forming a brake shoe normally held against the brake element, said finger adapted under the action of heat to stretch and disengage the brake shoe from braking engagement with the brake element.

In witness whereof I have hereunto set my hand.

CHARLES EDWARD ORMSBY. 

